INVESTMENTS - Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net Investment Income [Line Items]
Gross investment income	$ 161,920	$ 94,888	$ 447,391	$ 291,971
Investment expenses	(7,719)	(6,711)	(22,589)	(20,227)
Net investment income	154,201	88,177	424,802	271,744
Fixed maturities
Net Investment Income [Line Items]
Gross investment income	133,006	87,364	375,659	224,780
Other investments
Net Investment Income [Line Items]
Gross investment income	312	(7,576)	(4,543)	32,801
Equity securities
Net Investment Income [Line Items]
Gross investment income	3,050	2,490	8,495	7,349
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	8,892	6,256	26,158	15,323
Cash and cash equivalents
Net Investment Income [Line Items]
Gross investment income	14,465	5,350	35,638	10,147
Short-term investments
Net Investment Income [Line Items]
Gross investment income	$ 2,195	$ 1,004	$ 5,984	$ 1,571

The net gain or loss (both realized and unrealized) related to investments in certain entities that calculate net asset value per share and the amount after accretion (amortization) of discount (premium), of interest income and dividend income on nonoperating securities.

No definition available.

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The net gain or loss (both realized and unrealized) related to investments in certain entities that calculate net asset value per share and the amount after accretion (amortization) of discount (premium) of interest income and dividend income on nonoperating securities, net of investment expense.

+ References

No definition available.

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- Definition

Amount of expenses related to the generation of investment income.

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-Topic 946
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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